eQUEST® is a widely used, time-proven whole building energy performance design tool. Its wizards, dynamic defaults, interactive graphics, parametric analysis, and rapid execution make eQUEST uniquely able to conduct whole-building performance simulation analysis throughout the entire design process, from the earliest conceptual stages to the final stages of design. eQUEST's simulation engine, DOE 2.2, is also time-proven, well known, and widely used. Screen Shots


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eQUEST has been tested according to ASHRAE Standard 140. Results are available at www.doe2.com.

Expertise Required

For wizard-based use, virtually no experience with energy analysis is necessary. To use eQUEST's Detailed Interface, however, knowledge of building technology is required. Experience with other energy analysis simulation tools, especially DOE-2 based tools, is helpful.


eQUEST is one of the most widely used building energy simulation programs in the United States. The number of full program downloads averages approximately 10,000 annually.


The primary audience consists of building designers, operators, owners, and energy/LEED consultants. eQUEST is also widely used by regulatory professionals, universities, and researchers.


Inputs can be provided at three levels: schematic design wizard, design development wizard, and detailed (DOE-2) interface. In the wizards, ALL inputs have defaults (based on the California Title 24 building energy code).


Graphical summary reports provide a single-run results summary, a comparative results summary (compares results from multiple separate building simulation runs), and parametric tabular reports (compare annual results by endues, incremental or cumulative results). Additional output includes input/output summary reports (rule-of-thumb and other indices), nonhourly simulation results (tabular/text DOE-2 SIM file reports), hourly simulation results (text and comma-separated variable hourly listings for thousands of simulation variables), and California Title 24 compliance analysis reports.

Computer Platform

Microsoft Windows 98/NT/2000/XP/Vista

Programming Language

Interface: C++, DOE-2.2 engine: FORTRAN


The unique strength of eQUEST is that it is an energy performance design tool that evaluates whole-building performance throughout the entire design process. Its wizards (schematic, design development, and energy efficiency measure) make it possible for any member of the design team to explore the energy performance of design concepts from the earliest design phase. Its detailed interface (a full-featured Windows front-end for DOE-2.2) supports detailed analysis throughout the construction documents, commissioning, and postoccupancy phases. Its execution speed makes it feasible to perform many evaluations of large models, capturing critical interactions between building systems at the whole-building level. Its rule-based processor provides intelligent dynamic defaults in the interface and enables automated quality control checks of simulation inputs and results and automated Title 24 compliance (certified by the California Energy Commission for use with the 2001 and 2005 Title 24 compliance analysis) and automated Savings By Design analysis (a California new construction efficiency incentive program).


Defaults and automated compliance analysis has not yet been extended from California Title 24 to ASHRAE 90.1. It does not yet support SI units (I-P units only). Ground-coupling and infiltration/natural ventilation models are simplified and limited. Daylighting can be applied only to convex spaces (all room surfaces have an unrestricted view of each surface) and cannot be transmitted (borrowed) through interior glazed surfaces. Custom functions in DOE-2.1E (allows users limited customization of source code without having to recompile the code) have not yet been made available in DOE-2.2 or eQUEST.



James J. Hirsch and Associates


12185 Presilla Road
Camarillo, CA 93012-9243
United States






eQUEST is supported primarily through public funding from California's Savings By Design (www.savingsbydesign.com) and Energy Design Resources (www.energydesignresources.com), and is available at no cost from www.EnergyDesignResources.com and www.doe2.com. Long-term average weather data (TMY, TMY2, TMY3, etc.) for 1000+ locations in North America are available via automatic download from within eQUEST (requires Internet connection).